Abstract TP263: Acute Anemia After Intracerebral Hemorrhage Associates with Impaired White Matter Connectivity

Background/Objective: While chronic anemia is known to impair white matter connectivity and cerebrovascular disease, the effects of acute anemia on white matter connectivity are unknown. We assessed whether the acute, rapid anemia seen after intracerebral hemorrhage (ICH) is associated with MRI evidence of impaired white matter connectivity. Methods: Supratentorial spontaneous ICH participants enrolled in a prospective observational diffusion MRI (dMRI) study between 2017 and 2021 were assessed. Participants with available dMRI imaging and serial hemoglobin measurements during their hospitalization were analyzed. Acute hemoglobin changes from admission to MRI acquisition was the primary variable of interest. Impaired white matter connectivity was assessed as the radiographic outcome using quantitative anisotropy (QA) on dMRI data reconstructed with generalized Q-sampling Imaging (GQI) in the contralateral hemisphere to the ICH. Associations between hemoglobin changes and white matter connectivity were evaluated using a multivariate, non-parametric, permutation-based statistical framework (Correlational Tractography), adjusting for demographics and ICH volume, to obtain false discovery rate (FDR) corrected p-values for tract segments significantly associated with the study variable. Results: The 38 ICH patients with both MRI and hemoglobin data were predominately male (68%), had a mean age of 67 years (±13), and 65.8% had an ICH deep location. The median day of the MRI was 4, and the mean hemoglobin at baseline and time of MRI was 13.5g/dL (± 2.1) and 12.9g/dL (± 2.1), respectively. While baseline hemoglobin did not relate to white matter connectivity, greater acute hemoglobin decrements were associated with lower QA (FDRp <0.001), indicating impaired white matter connectivity. This observation was noted in several white matter pathways. Conclusions: Acute anemia following ICH associates with impairments of microstructural white matter connectivity. Further investigation is needed to understand whether these relationships impact clinical outcomes and whether anemia treatments can improve neuroimaging and clinical ICH outcomes.